LAS VEGAS - The District of Columbia has won back-to-back Miss USA titles.

Kara McCullough, a 25-year-old scientist working for the US Nuclear Regulatory Commission, was crowned Monday at the Mandalay Bay Convention Center on the Las Vegas Strip. She will go on to compete on the Miss Universe contest.

"I'm extremely thankful for this opportunity," she said after the event. "I just want to encourage so many women nationwide to find their passion in any subject possible and understand that nothing is difficult if you really, truly put the work in for it."

Fifty-one women representing each state and the nation's capital participated in the decades-old competition. The runner-up of the night was Miss New Jersey Chhavi Verg, a marketing and Spanish student at Rutgers University, while the second runner-up was Miss Minnesota Meridith Gould, who is studying apparel retail merchandising at the University of Minnesota.

McCullough was born in Naples, Italy, and raised in Virginia Beach, Virginia. She said she wants to inspire children to pursue careers in the fields of science, technology, engineering and mathematics.

The beauty pageant this year included five women who immigrated to the US at a young age and now as citizens hoped to represent the nation on a global stage. Verg and the women representing Florida, North Dakota, Hawaii, Connecticut and New Jersey told The Associated Press this week they have faced challenges and opportunities as immigrants.

Verg told The Associated Press days ahead of the competition that she and her parents immigrated from India to the U.S. with only $500 in their pockets when she was 4 years old. Her first winter she did not have a winter coat and the family struggled to adjust.

"I want to show Americans that the definition of what it means to be American is changing," the 20-year-old said. "It's not just one face. There are many different people who are Americans, and I feel like Asian-Americans often times are left out of the conversation."

Now that her preparation toward the pageant is over, McCullough said she is looking forward to eating a Texas cheesesteak at Waffle House.

"All you need is mayonnaise," she said. - AP